i have google map api on site a added a select to map page and add filter on basis on onchange event

selectedMarker = function (val) {
     var value = $(this).find(":selected").val();
    for (i = 0; i < map.markers.length; i++) {
        marker = map.markers[i];
        
        if (marker.name == value || name === 0 ) {
            marker.setVisible(true);
            
            } 
        else {
        marker.setVisible(false);
            }
        
    }  
   
}

and on html i have

<select id="selectschool" class="sort" onchange="selectedMarker(this.value);" >
            <option value="">Search by School</option>
            <option value="0">All</option>

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